I'm introducing myself to set theory. My reference doesn't seem to address the fact that 1/1 = 2/2 = 1. If we make a correspondence between natural numbers and rational numbers using sequential fractions, should we just skip equivalent fractions so as to make it a bijection? In other words, does it matter whether the correspondance is injective or not, or whether it is surjective or not?(adsbygoogle = window.adsbygoogle || []).push({});

I'm also wondering how one would prove that the set of real numbers in base ten is identical to the set of real numbers in another base.

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# Elementary set theory

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